Homes from the earlier end of that 1938-1994 range often still run one-piece tilt-up doors on side-mounted torsion hardware, or old extension springs strung along the horizontal track with no containment cable. Both are parts categories that most suppliers stopped stocking new decades ago, so a repair sometimes means adapting a modern part rather than dropping in an exact match.
Houses built from the 1960s onward, which make up most of the stock in this part of the service area, are more likely to have standard torsion springs centered over the door and a sectional panel door that takes off-the-shelf hardware. Those are more straightforward repairs.
The cold winters here matter regardless of the house's age. In a cold climate, steel torsion springs lose a bit of tension as temperatures drop, and nylon rollers get brittle and crack faster than they would in a milder region. If your door has gotten harder to lift by hand once it's below freezing outside, that's usually the spring, not the opener, and it's worth having someone look at the coil before it lets go entirely.